三铰拱
/ˈθɹɛdɪd ˈɹɒd/
n
English: three-hinged arch · 三铰拱
English · three-hinged archEspañol · arco de tres articulacionesFrançais · arc à trois articulations
释义：Arch with three roller joints: one at each end and one at the center.
English: three-hinged arch · 三铰拱